Left handed! you bet and one thing I hate is southpaw - Did you know that a sewing machine is built for left handers? You Bet - just sit down and experience it, Your left hand is always Free. Before electric typewriters etc the manual machines were the same way - you threw the carriage with the left - the docs you were typing were on the left- all that info was given me by my teacher a right hander. Me the left hander won state typing no errors 87 Words per minute no errors, manual Royal typewriter.
I learned to knit and crochet sitting across from my mom (mirror image) - The only thing I do right handed are scissors because when I was a kid we never heard of left handed ones.
I'm still a tad defiant cause back in the day left handers were considered by many to be mentally deficient.
So let her be and just teach and please please please stop pointing out to her - her left handedness - after all she's in her right mind! To coin Dr Seuss "Oh The Places You'll Go".